A senior police investigator was prevented from questioning Sinn Fein’s Martin McGuinness about the IRA’s Poppy Day bombing in Enniskillen after the Government said it “would not be a good idea”, a Westminster committee has been told.

A victims campaigner made the claim during an evidence session of a select committee inquiry probing how the Government handled efforts to gain compensation from Libya for IRA victims bereaved or injured by bombs manufactured with explosives provided by the late Colonel Gaddafi.

Kenny Donaldson, spokesman for umbrella group Innocent Victims United (IVU), said the IRA outrage on Remembrance Sunday 1987 was part of a Libyan strategy to use the republican organisation to wage war against the UK.

Eleven people who had gathered to pay their respects to the war dead were killed in the no-warning IRA bomb in the Co Fermanagh town.

Another victim died 13 years later having never woken from a coma. No-one has ever been brought to justice for the Enniskillen bomb.

Mr Donaldson told the Northern Ireland Affairs Committee hearing that the IRA were “quite content” to be Gaddafi’s “subcontractors” in his efforts to bring terror to the streets of the UK.

The Cenotaph at Enniskillen in the aftermath of the Poppy Day bombing

He added: “The reality is Enniskillen was the first significant atrocity where that was being put to test.

“The individuals who were involved in that, this goes right to the heart of all of this. We have also been advised by a senior former HET (historical enquiries team) investigator that he had cause to wish to bring in the deputy first minister (Mr McGuinness) for questioning in regards to that atrocity.

“He was prevented from doing so. The NIO (Northern Ireland Office) advised that that would not be a good idea. And it didn’t happen.”

Mr Donaldson did not provide a date for the alleged episode.

A Sinn Féin spokesperson rejected the claim. They said: “Martin McGuinness totally rejects this attempt based on unsubstantiated hearsay to link him to the Enniskillen bombing.”

The HET was set up in 2005 to re-examine about 3,000 unsolved Troubles murders. The specialist unit, which was independent from the Police Service of Northern Ireland, was wound up last year.

Mr McGuinness has previously admitted to being an IRA leader in Derry in the early 1970s but has insisted he left the organisation in 1974.